I'm using the MySQL Connector/C++ library to insert values into a database table. I'm following the examples at
http://dev.mysql.com/tech-resources/articles/mysql-connector-cpp.html
almost exactly. However, I can't seem to get prepared statements to work with value placeholders.
sql::mysql::MySQL_Driver* driver = sql::mysql::MySQL_Driver::Instance();
boost::shared_ptr<sql::Connection> conn(driver->connect("localhost", "", ""));
conn->setSchema("TESTDB");
boost::shared_ptr<sql::Statement> stmt(conn->createStatement()开发者_如何学C);
stmt->execute("DROP TABLE IF EXISTS TESTTBL");
stmt->execute("CREATE TABLE TESTTBL (m_id INT)");
boost::shared_ptr<sql::PreparedStatement> pstmt(conn->prepareStatement("INSERT INTO TESTTBL VALUES(?)"));
for (int i = 0; i != 10; ++i) {
pstmt->setInt(1, i);
pstmt->executeUpdate(); // Always inserts 0.
}
Any ideas on why I can't bind to the prepared statement? The other set* functions have the same result (e.g. if I use setString I get a string '0' in the resulting row).
I haven't done SQL in a while, but I think you're forgetting to put the column name there. The syntax should be:
INSERT INTO TESTTBL (column_name) VALUES (?)
If you wanted to insert into multiple columns, you'd use comma delimiters:
INSERT INTO TESTTBL (col1, col2, col3) VALUES (?,?,?)
Recompiling the C++ connector from source fixed this problem.
Probably a compiler setting in their pre-built binary that didn't agree with my project. I will talk to MySQL about this.
Thanks for the assistance.
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